seems like this forum is SUPER inactive. I just joined about a week ago..
Anyway, I first bought 10w-40, but then read that it may be the worst for our 250's (I own an '07). I read on ninja250.org(most amazing website ever for our bikes. It should become your best friend) that most people use Shell Rotella T6 full synthetic 5W-40. Apparently it's made for big farm equipment, but works great on the 250. Just put it in my bike about a week ago. Just letting you know what I use.
http://faq.ninja250.org/wiki/Preferred_Brands
What type of oil you use may depend on where you live and the climates though. You should find a local forum of motorcyclists or ask a friend what kind they use.
Anyway, I first bought 10w-40, but then read that it may be the worst for our 250's (I own an '07). I read on ninja250.org(most amazing website ever for our bikes. It should become your best friend) that most people use Shell Rotella T6 full synthetic 5W-40. Apparently it's made for big farm equipment, but works great on the 250. Just put it in my bike about a week ago. Just letting you know what I use.
http://faq.ninja250.org/wiki/Preferred_Brands
What type of oil you use may depend on where you live and the climates though. You should find a local forum of motorcyclists or ask a friend what kind they use.